Scraping disk



March 27,v 1951 E. KORBEL SCRAPING DISK Filed Dec.

INVENTOR ATTORNEYj Patented Mar. 27, 1951 2,546,546 y l my?, L

SCRAPINGDISK v The present invention relates to a scraping disc for roughening the marginal portions of the upper leather and sole so as to secure stronger adw herence of the glue in the manufacture of glued footwear. rEhe scraping discs hitherto known for this purpose are provided usually around their periphery with a removable abrasive strip or band, e. g. of paper or cloth coated with glass powder or the like. The principal disadvantage of the scraping discs of this kind resides in the rapid wear of the abrasive strips or bands and as a consequence in the loss of time in themanufacturing process, since it is necessary to exchange frequently the worn abrasive strips. If the abrasive strip breaks during the working process, as it has frequently happened hitherto, when no attention has been paid to this possibility, the broken strip may seriously injure the assistant during his work.

For the above reasons, rubber scraping discs have been used in some cases with thin steel wires anchored in the rubber. Since concurrently with the wear of the steel wires, the disc itself becomes worn out, it is not necessary to renew the abrasive surface of the disc and there is no danger of injury as with the first mentioned construction of the scraping discs. But this apparent advantage does not counterbalance the losses which arise due to the relatively large waste of rubber in the gradual abrasion of the disc proper and to the continuously diminishing scraping effect as a consequence of the reduction of the circumferential speed with the decrease of the diameter of the disc due to the wear to the latter.

All'the disadvantages referred to are eliminated by the scraping disc in accordance with the present invention. The main feature of the invention resides in that the scraping disc consists of two circular plates having provided be tween the same at their peripheries a plurality of sets of small scraping wheels freely rotatable about their own axes, which latter are arranged out of parallelism with the rotational axis of the circular plates.

An example of a scraping disc in accordance with the present invention is shown by way of example in the accompanying drawing in' which Fig. l is a top view of a portion of the disc periphery in development;

Fig. 2 is a side view partly broken away to show the small scraping wheels; and

Figure 3 is a sectional view through a portion of the assembly of Fig. 2 showing the mounting of the scraping wheels. Y

4 Claims.

Application December 3, 1948, vSerial-bidi r In ICzechoslovakia Decemberl1, 1947 wiege; i

Referring to the drawing, the scraping disc shown comprises a number of sets of small scraping wheels I consisting each of individual metallic star wheels 2 which are mounted on pins 5 and, if desired, may be separated from each other by means of spacing rings 4. The stars 2 and the spacing rings 4, if any, are mounted for free rotation on the pins 5, the openings 3 in the stars 2 being substantially larger than the diameter of the pins 5.

The pins 5 are rigidly held at their one extremity in wedge-shaped projections 6 provided on the circular plates 1 and at their opposite extremity are inserted in recesses 8 formed in wedge shaped projections 9 on the other circular plate HJ. The two plates 1 and I0 are provided each with an aperture il by means of which they are mounted on a shaft, and are clamped together by means of bolts I2.

The scraping eifect of the disc in accordance with the present invention is uniform because the stars 2 which are urged outwards by the centrifugal force, yield softly during the scraping operation, and if the pressure of the material to be roughened incidentally increases, they give away so that an undesired scraping through the whole thickness of the material cannot take place.

What I claim is:

1. In a scraping disc, more particularly for roughening the marginal portions of the upper leather and sole to improve the adherence of the glue in the manufacture of glued footwear, the arrangement of two circular plates having mounted between the same at the peripheries of the plates a plurality of sets of small scraping wheels freely rotatable about their own axes upon engagement with the surface to be rough-v ened, the said axes being arranged out of parallelism with the rotational axis of the circular plates. y

2. In a scraping disc, more particularly for roughenlng the marginal portions of the upper leather and sole to improve the adherence of the glue in the manufacture of glued footwear, the arrangement of two circular plates having mounted between the same at the peripheries of the plates a plurality of sets of small scraping wheels freely rotatable about their own axes upon engagement with the surface to be roughened, the said axes being arranged out of parallelism with the rotational axis of the circular plates, the small scraping wheels consisting of metallic star wheels mounted for free rotation on pivot pins.

3. In a scraping disc. more particularly for roughing the marginal portions of the upper leather and sole to improve the adherence of the glue in the manufacture of glued footwear, the arrangement of two circular plates having mounted between the same at the peripheries of the plates a plurality of sets of small scraping wheels freely rotatable about their own axes upon engagement with the surface to be roughened, the said axes being arranged out of parallelism with the rotational axis of the circular plates, the small scraping wheels consisting of metallic star wheels mountedv4 for free rotation on pivot pins, which are intimated between the circular plates and are held in position by clamping the latter together by means ot bolts.

4. In a scraping disc, more particularly for roughening the marginal portions of the upper leather and sole to improve the adherence oi the glue in the manufacture of glued'iootwear, the arrangement of two circular plates having mounted between the same at the peripheries of the plates a plurality of sets of small scraping wheels freely rotatable about their own axes upon engagement with the surface to be roughened, the said axes being arranged out of parallelism with the rotational axis of the circular plates, the small scraping wheels consisting of metallic star wheels mounted for free rotation on pivot pins, which are mounted between the circular plates and are held in position by clampingrthe latter together by means of bolts, the scraping star wheels of each set being separated from one another by means of spacing rings.

BEDRICH KORBEL.

No references cited. 

